You may not see arcing. The problem could be induction crossfire and that is why the wire routing is so critical.

 

The wires I have now are ford motorsports 8mm...probably 3-4 years old at the most.

 

You mean the 9mm ones? I should have looked at the pic before I asked. My apologies. I'm also running the same set. Love 'em. However, I'm pretty **** about plugs and plug wires. I have been doing so many different mods over the past few years, that I'm continuously pulling the plugs and wires out. Because of this, I won't keep the same plug wires in for more than 2 years. High quality or not. I'd go ahead and swap them out if they're that old. Even high quality ones don't "handle" well at that age. Especially since you're running the aftermarket coil and MSD box. Even if it doesn't fix your problem, it's a good time to replace 'em.

 

Well today I replaced the #5 spark plug. I thought maybe the proceline was cracked and allowing it to arc to the block. I changed my plugs about 3-4 weeks ago, but left plugs 3+4 alone because it was too much of a pain to get to and my motor is coming out in a few months anyway so I decided to leave it. I decided to change them, I replaced #3 and I'll change #4 tomorrow. I moved the wires a little bit, not really, and whatever I did today improved the situation. So maybe it's just the two old plugs that were in the motor causing it to skip that bad, not sure, but I'll change the 4th one tomorrow and see what happens. Thanks.

 

OK Update time.

I have put a new cap/rotor and new wires in it and replaced all the plugs. Has not fixed the problem. The plugs are gaped at .056 (msd ignition too) and are just motorcraft plugs. I have all the wires separated and they're wiring should be fine. I thought the new cap/rotor might help but it didn't. I'm at a loss and might have to bring it in to the shop. The problem changes. At first it was a slight miss on hills, then a heavy miss on acceleration in any gear at more than 1/2 throttle. Now it's pretty much missing all the time and you can hear the motor just not burning the fuel correctly. I have no idea what to do.

 

Well, I might be able to lead you somewhere.

Within, oh, about a year and a half my MSD's TFI coil started making just about the very same events happen to my truck. It did seem there might be some weird low RPM that it wanted to run at, but not really.

I was stumped.

After working on it at the side fo the road and giving up, I limped it home and tried one more time. Now it was way more quiet at home, and I thought I heard a ticking sound. Looked down into the engine bay at the I-6's MSD coil and saw arcing from the top seal to an electrode (or something like that).

Replaced it and all is fine.

What made the old one go? It may have been age (1.5 years), it may have been the severe rain I was driving through that day, or it might have been faulty (am I missing anything here?). Justin, can you remember driving through rain right before this happened?

it's just a thought...

Best,
GammaDriver

 

No, but if you look at my coil at night you can see sparks between the actual body of the coil windings and that metal ring around the outside....I do have the MSD TFI coil....

 

Well I don't know what to tell you about that - if you're seeing sparks on the outside of the coil then I don't think that's good.

In fact, I beleive you and I got our MSD ignitions and coils at about the same time. You may find that the tops of the MSD TFI coils have been slightly changed from your current design, and that may be because of the problem that I had.

Best,
GammaDriver

 

Ya I've had mine for awhile. Maybe I'll swipe the coil of my dads truck and see if it does anything.

 

Well heres another update.

Like 5-6 days ago the engine was running great, I didn't do a thing to it after the post above yet, and it was running perfectly fine for like 4-5 days. Yesterday on my way home it started skipping again and today it's just running like crap again. So obviously it's something variable since I didn't do a thing with it and weather doesn't seem to have an effect on it. I changed the cap/rotor/wires/spark plugs, so all of those must be fine since it was running correctly at one point in the last week. I guess I can change out the coil with my dads and see what happens, but I don't know why it run like crap..then run fine...the run like crap again.

It's really weird because sometimes it's just a big miss but otherwise the engine sounds normal...and sometimes its several misses....and sometimes the engine is gargling (exhaust note change) as the fuel isnt being burned properly....really weird.

 

Yeah, that's weird. I don't have an answer (save for trying a new coil, which I still suggest because it is easy to do).

Come to think of it (and this is pushing it here, admittedly), there was one time one or two months before my truck's coil went south that I thought I ran out of gas (I was, admittedly, way lower on fuel than I ever run). After doing the get-gas-can/fill-gas-can run-around thing I was able to get it chugging then running. But the thing was that the event happened in a big rain storm (of course), so it could have been the coil shorting itself out.

That last time I mentioned (previously in this thread) was right after a big rain event with me plowing through big puddles like a redneck. (luckily within 25 miles of Summit Racing, so i convinced my dad I had to go to Summit to spend money)

So mine may have been intermittent (with water).

But all that, plus the fact that MSD went and redesigned the coil tops on MSD coils, tells me that MSD TFI coils had a weakness that needed addressed.

Perhaps that small of a coil - which is in such close proximity to a nice conductive piece of steel (the mount) - was too much to bear for the old MSD TFI coils and eventually a spark would punch through to make the short? I don't know.

Best,
Dave

 

I'll try my dads coil and see if that helps any. Next step is the mechanic.

 

I don't like this talk about the msd tfi coil I just put one on my truck a few months ago. It was new. Hopefully I have the improved design. Any quick way to tell?

Sorry to take the thread off topic.

 

I will have to check to see my current design to jog my memory. That will have to be during daylight, so it ain't gonna be now - sorry.

I think I remember that the last one I had was - possibly - not black on the entire top of the coil? (in looking at the pictures the black seems to be a sealant?).

I think I bought the system in 2002, so there's that.

 

Hey Justin, did you ever get a chance to pull the codes?